Manufacture of brake shoes



June 20, 1933. L. E. LA BRIE 1,914,997

MANUFACTURE OF BRAKE SHOES Filed Oct. 6, 1928 2 Sheets-Sheet 1 IN VEN TOR.

LUDGER E. LA BRIE A TTORNEYS.

INVENTOR. v LUDGER E. LA BRIE ATTORNEYS.

Patented a. '20, 1933 UNITED STATES PATENT OFFICE LUDGEB 3. LA, BRIE, OF SOUTH BEND, INDIANA, ASBIGNOB 'I'O BENDIX BRAKE OOIPANY, OF SOUTH BEND, INDIANA, A GOBPOBATION OF ILLINOIS IANUFAGIUBE OF BRAKE SHOES Application filed mm 0, 1929. Serial No. amass.

This invention relates to brakes, and is described in connection with the manufacture from sheet steel of the shoes, of an internal expanding automobile brake. An object of l the invention is to provide an inexpensive method of making a light but very strong type of brake shoe, preferably by drawin s set metal through a die to fold it on tsel to provide the rims of the shoes and su table stiffening webs therefor.

The above and other objects and features of the invention, including various novel and desirable details, .will be apparent from the following description of the illustrative method and article shown in the accompanyin drawings, in which:

igure 1 is a vertical section through a brake, just inside the head of the brake drum, and showing my novel brake shoes in side ele- Vation;

Figure 2 is a section through the primary shoe of the brake, on the line 22 of Figure 1 Figure 3 is a section through the secondary shoe of the brake, on the line 3-3 of Figure 1; Figure 4 is a section through the primary shoe adjacent its pivoted end, on the line 4-4 of Figure 1; v

Figure 5 is a side elevation of a die with the sheet metal being drawn therethrough;

Figures 6', 7 8, and 9' are respectively sections on'the lines 6-6, 7-7, 8-8, and 9-9,

of Figure 5, showing various stages of the drawing operation; and

' Figures 10, 11, and 12 are similar sections showing successive stages of the drawing of' a secondary shoe.

The illustrated brake includes a rotatable drum 10, at the open side. of which is a sup port such as a backing plate 12, and within 42 which is the friction means of the brake. In

this particular brake the friction means includes primary and auxiliary shoes 14 and 16, T-shaped in cross-section, and an intermediate secondary-shoe 18 having two spaced stiffening webs straddling the lower ends of shoes 14 and 16.

Shoe 14 is connected to the secondary shoe 18 by a floating pivot 20, while the secondary shoe in turn is anchored on a fixed pivot 22 passing through a relatively large opening shoes 14 or 16.

in the web of shoe 16. Shoe 16 is anchored on a fixed pivot 24 passing through relatively large openings in the webs of the shoe 18. The applyin means and the return springs, being of we l-known construction, are not herein shown. The shoes are faced with the usual friction lining riveted or otherwise secured thereto, the faces of the shoes preferably bein knurled or serrated or otherwise roughene to hold the lining against creeping.

According to an important feature of the present invention, the shoes are formed in a novel manner by folding sheet steel b drawing it through a forming die. In igures 5-9 I illustrate the formation of one of the In this process, the'sheet metal S is first drawn over a mandrel 28 which gradually changes from a rectangular cross-sectional form as shown in Figures 6 to a triangular section as shown in Figure 7, the sheet steel being drawn throu h a die 30 of corresponding shape. Die 30 is made up of suitable sections secured together in any desired manner, and may be provided with passages 32 for the circulation of a lubricating fluid.

It will be seen that the metal is first drawn to a channel form, and the walls of the channel are then folded in upon the base of the vchannel (Figure 9), thus giving a d0ublethickness rim and a double-thickness stifi'enin web.

ngths are next severed from the formed material and bent into arcs in any desired manner. The excess material of the rim is cut away at the lower end of the shoe a cam plate 34 is secured at the upper en rein-- parallel pairs of adjoining portions, thewings bein bent down against the sides of the channe to form two double-thickness stifiening webs. As before, lengths are cut and bent on arcs, the excess rim material 13 cut away, and holes for anchors 22 and 24 and for pivot 20 are punched or drilled.

It is not my intention to limit the scope of my invention to the manufacture of the particular shoes described, or otherwise than by the terms of the appended claims.

I claim:

1. That method of making a brake-shoe segment which comprises drawing sheet metal through a die to form it first into a channel having walls and a base, and then further drawing it to fold the walls of the channel underneath the base to form a double-thickness rim portion and a double-thickness web between the edges of the rim portion.

2. That method of makin a brake-shoe segment which comprises rawing sheet metal through a die to form it first into a channeLhavmg walls and a base, and then further drawing it to fold the walls of the channel underneath the base to form a rim portion and a web. 7

3. That method of making a brake-shoe segment which com metal through a die to vide a base and a lated portions, portions together by drawing through a second die to form a double-thickness stiffening web ri 'dly secured to said base.

4. at method of makin a brake-shoe segment which comprises drawing sheet metal through a dieto fold the metal to provide a base and two parallel airs of adjoining portions, pressing the si es of said por= tions to ether by drawing through a second die and subsequently bending the drawn metal into .an arc to form two double-thick- 888 stifiening webs rigidly secured to said ase.

5. That method of makin a brake-shoe segment from sheet metal 0 less thickness than the thickness of a component part of the completed segment, which comprises drawing the sheet metal through a die to form a channel having sides and a base, bend the sides of the channel intermediate their e5 pressing certain of the bent portions into intifold the metal to propluralityof angularly remate contact to form a double-thicknes web.

and bending the structure so formed on an arc.

6. That method of forming a brake-shoe 7. That method of making a brake-shoe .segment which comprises drawing sheet metal through a die to fold the metal to provide a base and a pair of sides symmetrical with respect to each other, folding the sides along the central portion thereof, and pressing a portion of t e sides together to form a double-thickness sti'fiening web, and bending the structure so formed on an arc.

In testimony whereof, I have hereunto signed my name.

LUDGER E. LA BRIE.

prises drawing sheet and pressing the sides of said segment from sheet metal of less thickness than the thickness of a component part of the completed segment, which com rises drawing the sheet metal through a die to form a channelhaving sides and a flat base, bending the sides intermediate their edges, pressing certain side portions into intimate contact to 

